The largest rainforest in the world, the [I 013 / Amazon rainforest] lies in the tropical region of northern South America. It is named after the [L2 401 / Amazon River] which runs through the region and drains the massive [L2 402 / Amazon Basin]. It is located in the largest river basin in the world, extending over 2,700,000 square miles. The area within the Amazon Basin is sometimes referred to as [M 003 / Amazonia].
About half of Amazonia is found in Brazil; the other half crosses into eight other countries - Guyana, Venezuela, Surinam and French Guiana to the north and east, Colombia to the northwest, Peru and Ecuador to the west, and Bolivia to the south.
THE CLIMATE OF THE AMAZON BASIN:
The Amazon Basin lies in the tropical region between the equator and the tropic of Cancer. This region is characterized by high temperatures and [L2403 / I003 / heavy rainfall throughout the year]. On average, the temperature in the Amazon rainforest is 80 degrees Fahrenheit, and between 120 and 240 inches of rain fall annually.
Night-time temperatures are somewhat lower, dropping to around 68 degrees Fahrenheit. There is little temperature difference between the months and the only seasonal differences are in the amount of rainfall, not in the temperature. The relative humidity remains high throughout the year. Climate and vegetation growth are mutually dependent. It is this combination of moisture and warmth which aids rapid plant growth, hence the density of rainforest vegetation.
RAINFORESTS AND CLIMATE CONTROL:
Tropical rainforests form a green belt around the earth. They perform several vital environmental functions which control both local and global climates.
Rainforests are essential in keeping their locale moist. They act as giant sponges for the large amounts of rain which fall on them, soaking up the moisture and gradually releasing it into rivers and lakes. This process is called 'watershed' and enables a constant supply of clean water to reach rivers and lakes for irrigation. They are also instrumental in keeping other areas moist. Tropical rainfall helps regulate global rainfall patterns. Land which is hundreds or thousands of miles away from the rainforests is affected by them.
Rainforests also play an essential part in regulating [L2 404 / the earth's atmosphere]. The gases in the atmosphere control the amount of sunlight that reaches the earth. These must be kept in balance for living things to survive. If there is either too much or too little sun, all living things will die. Trees act as the earth's lungs, managing the amounts of carbon dioxide and oxygen in the global atmosphere. Too much carbon dioxide in the atmosphere is poisonous for living creatures. Today, [L2 405 / man produces a great deal of carbon dioxide].
Rainforest trees absorb huge amounts of carbon dioxide during [G 22 / photosynthesis]. A rainforest tree is 50 percent carbon. Rainforest trees also release a great deal of oxygen to the atmosphere. One third of all the oxygen in the world is produced by rainforests. When the rainforest is destroyed, there are less trees to absorb carbon dioxide and release oxygen. In addition to this, [P 051 & P055 / burning trees release large amounts of carbon dioxide] into the atmosphere. The increase in carbon dioxide in the atmosphere is contributing to [L2 406 / global warming].
